X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Ftimesync%2Ftimesyncd-manager.c;h=a5678ccaed5ede60adadeeb5cb3132d916c1a809;hb=ba7408a6e9fa2f79f7e69052de78f82e12c613f6;hp=9b8b7d3eb6886790aba0cb2151806c4aa3c63b7c;hpb=3af0442c52090f34ae7a1c8e6b6587c540c06896;p=elogind.git

diff --git a/src/timesync/timesyncd-manager.c b/src/timesync/timesyncd-manager.c
index 9b8b7d3eb..a5678ccae 100644
--- a/src/timesync/timesyncd-manager.c
+++ b/src/timesync/timesyncd-manager.c
@@ -92,6 +92,9 @@
 /* Maximum acceptable root distance in seconds. */
 #define NTP_MAX_ROOT_DISTANCE           5.0
 
+/* Maximum number of missed replies before selecting another source. */
+#define NTP_MAX_MISSED_REPLIES          2
+
 /*
  * "NTP timestamps are represented as a 64-bit unsigned fixed-point number,
  * in seconds relative to 0h on 1 January 1900."
@@ -219,15 +222,18 @@ static int manager_send_request(Manager *m) {
                 return r;
         }
 
-        r = sd_event_add_time(
-                        m->event,
-                        &m->event_timeout,
-                        clock_boottime_or_monotonic(),
-                        now(clock_boottime_or_monotonic()) + TIMEOUT_USEC, 0,
-                        manager_timeout, m);
-        if (r < 0) {
-                log_error("Failed to arm timeout timer: %s", strerror(-r));
-                return r;
+        m->missed_replies++;
+        if (m->missed_replies > NTP_MAX_MISSED_REPLIES) {
+                r = sd_event_add_time(
+                                m->event,
+                                &m->event_timeout,
+                                clock_boottime_or_monotonic(),
+                                now(clock_boottime_or_monotonic()) + TIMEOUT_USEC, 0,
+                                manager_timeout, m);
+                if (r < 0) {
+                        log_error("Failed to arm timeout timer: %s", strerror(-r));
+                        return r;
+                }
         }
 
         return 0;
@@ -562,6 +568,8 @@ static int manager_receive_response(sd_event_source *source, int fd, uint32_t re
                 return 0;
         }
 
+        m->missed_replies = 0;
+
         /* check our "time cookie" (we just stored nanoseconds in the fraction field) */
         if (be32toh(ntpmsg.origin_time.sec) != m->trans_time.tv_sec + OFFSET_1900_1970 ||
             be32toh(ntpmsg.origin_time.frac) != m->trans_time.tv_nsec) {
@@ -726,7 +734,9 @@ static int manager_begin(Manager *m) {
         assert_return(m->current_server_name, -EHOSTUNREACH);
         assert_return(m->current_server_address, -EHOSTUNREACH);
 
-        m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
+        m->missed_replies = NTP_MAX_MISSED_REPLIES;
+        if (m->poll_interval_usec == 0)
+                m->poll_interval_usec = NTP_POLL_INTERVAL_MIN_SEC * USEC_PER_SEC;
 
         server_address_pretty(m->current_server_address, &pretty);
         log_info("Using NTP server %s (%s).", strna(pretty), m->current_server_name->string);
@@ -766,8 +776,11 @@ void manager_set_server_address(Manager *m, ServerAddress *a) {
         if (m->current_server_address == a)
                 return;
 
-        m->current_server_name = a ? a->name : NULL;
         m->current_server_address = a;
+        /* If a is NULL, we are just clearing the address, without
+         * changing the name. Keep the existing name in that case. */
+        if (a)
+                m->current_server_name = a->name;
 
         manager_disconnect(m);
 
@@ -872,6 +885,7 @@ int manager_connect(Manager *m) {
                         manager_set_server_name(m, m->current_server_name->names_next);
                 else {
                         ServerName *f;
+                        bool restart = true;
 
                         /* Our current server name list is exhausted,
                          * let's find the next one to iterate. First
@@ -888,6 +902,8 @@ int manager_connect(Manager *m) {
                                 f = m->link_servers;
                                 if (!f)
                                         f = m->system_servers;
+                                else
+                                        restart = false;
                         }
 
                         if (!f)
@@ -899,6 +915,25 @@ int manager_connect(Manager *m) {
                                 return 0;
                         }
 
+                        if (restart && !m->exhausted_servers && m->poll_interval_usec) {
+                                log_debug("Waiting after exhausting servers.");
+                                r = sd_event_add_time(m->event, &m->event_retry, clock_boottime_or_monotonic(), now(clock_boottime_or_monotonic()) + m->poll_interval_usec, 0, manager_retry_connect, m);
+                                if (r < 0) {
+                                        log_error("Failed to create retry timer: %s", strerror(-r));
+                                        return r;
+                                }
+
+                                m->exhausted_servers = true;
+
+                                /* Increase the polling interval */
+                                if (m->poll_interval_usec < NTP_POLL_INTERVAL_MAX_SEC * USEC_PER_SEC)
+                                        m->poll_interval_usec *= 2;
+
+                                return 0;
+                        }
+
+                        m->exhausted_servers = false;
+
                         manager_set_server_name(m, f);
                 }
 
@@ -1039,7 +1074,7 @@ static int manager_network_event_handler(sd_event_source *s, int fd, uint32_t re
         online = network_is_online();
 
         /* check if the client is currently connected */
-        connected = m->server_socket >= 0 || m->resolve_query;
+        connected = m->server_socket >= 0 || m->resolve_query || m->exhausted_servers;
 
         if (connected && !online) {
                 log_info("No network connectivity, watching for changes.");